1. Cross Reference
This application is related to application Ser. No. 589,905 filed concurrently herewith which also describes the dilatant mold apparatus and fluidized powder feed disclosed herein.
2. Field of the Invention
The invention is related to molds used in metal and ceramic powder forming and in particular to a mold and molding aparatus producing a dilatant motion which assists in the filling of the mold.
3. Prior Art
The use of metal powder forming for making relatively small intricate metal parts is finding acceptance in industry as more economical than die casting. As the formed parts become more complex, difficulties are being encountered in filling the molds with powdered material. To overcome these problems Helmrick et al, U.S. Pat. No. 3,743,468, and Chanlund, in U.S. Pat. No. 3,302,262, teach longitudinal vibration of the mold while applying pressure to the powdered material. Seil, in U.S. Pat. No. 1,995,947, further suggests transverse vibration of the mold. To further assist the distribution of the powdered material within the mold, Hirt et al, in U.S. Pat. No. 3,712,785, adds the concept of evacuating the mold to remove gas particles from between the interstices of the powdered material. In a different approach Maugweiler, U.S. Pat. No. 3,756,762, teaches a compacting apparatus for carbon rods in which the cover and bottom half of the mold are vibrated at different frequencies. However all of these approaches have only been successful with the molding of parts having relatively simple geometries but are unsatisfactory for the molding of parts with complex geometries.
The present invention is a dilatant mold and molding apparatus which is compatable with the molding of parts with both simple and complex geometries.